Background: Substance use disorders have become a widespread public health problem, especially in the northeastern states, and limited studies have been undertaken to reflect the picture of the same. Aims: The aim of the study was to study the sociodemographic and clinical profile of drug treatment seekers attending a State Psychiatric Hospital and De-addiction Center of Northeastern India. Materials and Methods: It was a cross-sectional hospital-based study conducted from October 2018 to August 2019. Two hundred and ten consecutive treatment-seeking patients, fulfilling inclusion and exclusion criteria and diagnosed with the International Classification of Diseases version 10 for substance dependence, were included in the study. Results: Most common abused drug was opioids (42.9%), followed by alcohol (14.3%), whereas 29.0% were people who inject drugs. Peer pressure in 55.2% and curiosity in 32.9% were reported to be the most common causes for initiating substances. Hepatitis C was the most common (52.4%) comorbidity related to intravenous drug users. Conclusions: Results of the current study will definitely encourage further large-scale community-level studies to assess the prevalence of substance abuse in the state as well as in drug policymaking.